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Posts Made By: Lorne Johnson

January 24, 2003 02:16 AM Forum: Equipment Talk

Advise onTerrestial Mount for C-8

Posted By Lorne Johnson
The Giro that Miguel gave the address for is certainly the first choice that comes to mind.

That or making a dobsonian type mount on a stand.

February 7, 2003 02:33 PM Forum: Equipment Talk

Best planetary views for under $600 (used)?

Posted By Lorne Johnson
There was an 8" f 6.85 Dob with the mirror made by Mike Spooner (see previous post) for sale on this board last night. I have an 8" f 5.7 mirror by Mike Spooner that is a wonderfull planetary scope.

The Mak Newts are also excellent, even the MN 56 which occasionally come up and go for around $600 for a good OTA. I have one of those also. It goes on an GEM which is nice for planetary.

There is an argument that scopes of 4 or 5 inch apeture do well on average seeing nights. There is some truth to this, but only some.

February 19, 2003 02:05 PM Forum: Maksutovs

MN Collimation Question

Posted By Lorne Johnson
I have a an MN 56 and had a similar immediate thought. In my case I wanted to springload the adjustment screws. I decided to deal with it the next time I needed to collimate it. But . . . that time has yet to come. If warranty matters, you might want to be careful. I believe that opening the tube may void it (letting any dealer certainly does).

February 22, 2003 04:48 PM Forum: Equipment Talk

S&T Reviews

Posted By Lorne Johnson
I don't think that you'll be dissapointed with your D&G. I've look through two 5 f/15 and 5 f/12, and they are gorgeous instruments. They do require a substantial mount though!

February 25, 2003 03:30 PM Forum: Equipment Talk

127/7.8 achro or 153/10 Mak Cass ???

Posted By Lorne Johnson
The Achro will probably have more false color than your Stellarvue. It will give you more similar wide views otherwise. Your eyepieces will keep doing roughly what they are now. You will need a good size mount for that longer heavier tube (this is important, and can be costly).

The Mak will give you higher powers, narrower field of view, and you will defeinitey want some kind of wide field 40 mm. There should be no false color, contrast may suffer somewhat (the good Russian scopes really do minimize this). The mount and vibrations will be less of a problem with that compact short tube.

A 5 inch MAK NEWT might give you the best of both worlds, depending on what mount you currently own.

A chaque a son gout (or something like that).

February 27, 2003 08:14 PM Forum: Telescope Making

Information on mirrors

Posted By Lorne Johnson
Discovery and University optics also have very good reputations for quality production mirrors.

February 28, 2003 12:08 AM Forum: Equipment Talk

7mm Nagler

Posted By Lorne Johnson
The 7 mm has cosiderably more eye relief and a larger eye lense, making it noticably more comfortable to use. I happen to have two f/6 scopes that work out to about 160x respectively with the 7 and 4.8. Optically they seem very similar, and very good.

February 28, 2003 03:54 PM Forum: Deep Sky Observing

M102 - How do you observe it?

Posted By Lorne Johnson
Since M102 does not exist as a separate Mesier object, it can be considered as the ultimate in a low surface brightness object. It is a duplicate of M101, which is also a fairly low surface brightnes object. Contrast is of the essences for this, but I have only seen it in a 5 inch scope, both a borrowed Tak MT 130 reflector, and an MN 56 Mak Newt. Getting it higher in the sky helps, as does a dark night. It is indeed like M33 in brightness, but much larger as I remember. I first found it with a Siebert standard 21 mm, so it doesn't require big bucks. It was best barlowed to 14mm, I think. I live under dark skys near Stellafane, but am certainly no O'Meara at the eyepiece.

March 1, 2003 01:56 PM Forum: Equipment Talk

Siebert Optics Eyepieces

Posted By Lorne Johnson
I own a 12.5 standard and a 21 mm standard. Both are good eyepieces with excellent on axis sharpness and very good across the field at f/6. I also own his variable barlow, which is an excellent barlow, although it requires a lot of outfocus above 2x. Contrast is very good, and could probably be improved with a little flocking paper in the barrel. They aren't the prettiest eyepieces to look at, but they are pretty damn good to look through.

Harry is very accessible and will really try to give you his best advice, so I would recommend either calling him or e-mailing him--just ask. Harry does all his own designing and building, so he understands optics. He has a 30 day return policy which he stands by, so he will be very up-front about how any individual eyepiece will work in your scope.

March 4, 2003 08:25 PM Forum: Equipment Talk

So Confused..9.25SCT,7"mak or 7" mak-newt

Posted By Lorne Johnson
The length of the MN 76 will require a very beefy (and therefore expensive) Equitorial Mount. The 9,25 mcuh less so. The MN 76 is, however, a very flexible scope, and you could cut down the cost considerably by building a dobsonian type mount for it.

At that point, though, the PDHQ 8" f/7 dobsonian (with 1.5 inch central obstruction) from Discovery starts to look pretty cost effective at $800 for the scope and mount. The views in all three will almost always be limited far more by atmosphere than scope.

Of course, at some point you have to take matters into your own hands, and tell us to get off.

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